This application relates generally to microsurgical systems and equipment used in ophthalmological surgery, more particularly, to a shuttered receptacle and plug assembly for the connection of a one or more fiber optic fibers to a single light source of a microsurgical system.
Microsurgical systems for use in ophthalmic surgery typically include one or more hand held instruments connected to and controlled by a control console. The hand held instruments include vitreous cutting and aspiration probes and suction cannulas such as the pneumatic vitrectomy device disclosed in the pending application Ser. No. 08/241,749, filed May 12, 1994, the disclosure of which is hereby incorporated by reference. The control console also contains a vacuum source for providing suction to the vitrectomy probe. Our pending application Ser. No. 08/255,659, filed Jun. 8, 1994 discloses a cassette and a vacuum aspiration collection system containing the cassette, the disclosure of which is hereby incorporated by reference.
In many types of opthalmological surgery a source of light is required. The light source is used to illuminate the surgical field. In ophthalmological surgery, particularly retinal surgery, the surgical field is inside the eye. External light sources tend to cause reflections from the cornea of the eye thus distorting the surgical field. Furthermore, when an external light source is used, the aperture available for penetration of the light into the surgical field is limited by the pupil of the eye. For these reasons, it is a common practice to use a fiber optic instrument to deliver light to the inside of the eye. By use of fiber optic instruments, corneal reflections and/or bums are substantially eliminated and the light my be pointed in any desirable direction.
Fiber optic instruments have been developed such that the instrument delivering the light casts the light directly on the surgical site. Sometimes it has been found desirable to combine the fiber optic instrument with another instrument. For example, the optical fiber can be combined with an intraocular scissors. Such combinations allow the surgeon to use both hands to manipulate the tissues instead of one hand to manipulate tissues and the other to direct the light. These multi-function instruments generally use a smaller optical fiber connected to a light source. Obviously it is an advantage to have the fiber optic light source contained in the same control console that drives the vitrectomy probe or other suction instrument.
Often the surgeon requires the use of more than one instrument. For example, the surgeon may use a suction forceps and an intraocular scissors at the same time. Likewise, the surgeon may employ a vitrectomy probe as well as a non-expandable gas delivery cannula when performing a pneumatic vitrectomy procedure. In these situations, it may be desirable to have an independent optic fiber for each instrument so that the surgeon can direct light to a particular area within the surgical site subject to the application of the particular instrument.
Furthermore, most light sources available for illumination of the optical fibers have a focal point that is much larger that the largest optical fiber in use. Consequently, the output of the fibers is directly proportional to the cross sectional area of the fiber. In other words, in a fiber having a diameter of 0.03 inch, the light output will be 2.25 times the output of a fiber having a diameter of 0.02 inch. Moreover, developments have enhanced the intensity of the white light used to illuminate optical fibers. Consequently, it becomes more important to have the ability to adjust the intensity of the light by dimming the light without distortion of the light. An apparatus for dimming the light provided by the optical fiber without affecting the light source is the subject matter of the co-pending parent application Ser. No. 08/255,660. It would be advantageous, therefore, to provide a white light dimmer for a single white light source incorporated in an ophthalmological surgery system that simultaneously accommodates multiple optic fibers.